After a year of consultations and over 4 million public comments, President Obama's Clean Power Plan will be finalised early next week.
The strategy will outline restrictions on CO2 from electricity that individual states will have to implement.
To give reluctant states more time to comply, the starting date is expected to be delayed by 2 years.
It's likely that new supports for renewable energy will also be announced.
In June last year the US Environment Protection Agency (EPA) first put forward its proposals for restrictions on power plants.
The EPA said that emissions from electricity generation need to be reduced by 30% of the 2005 level by 2030.
At that time the EPA said that individual states need to get their plans in place by 2016 and they were to become operational by 2020.
But after consultations with industry, states and 4.3 million comments from the public, the EPA is likely to extend the deadline for the start of carbon cutting until 2022.
But while some have seen the delay as a weakening of Obama's climate commitment, the White House Chief of Staff hinted that the new rules would actually make a bigger overall impact on emissions.
"There really is no overstating how big this year is for climate change," said Denis McDonough, speaking at a Washington forum earlier this week.
"We will finalise a stronger rule."
The thinking appears to be that a shorter deadline makes it more likely that states will switch from coal to natural gas, as they have been doing in recent years.